Appendix B – Region 3 Country and regional profiles of volcanic hazard and risk: Middle East and Indian Ocean S.K. Brown1, R.S.J. Sparks1, K. Mee2, C. Vye-Brown2, E.Ilyinskaya2, S.F. Jenkins1, S.C. Loughlin2* 1
University of Bristol, UK; 2British Geological Survey, UK, * Full contributor list available in Appendix B Full Download
This download comprises the profiles for Region 3: Middle East and Indian Ocean only. For the full report and all regions see Appendix B Full Download. Page numbers reflect position in the full report. The following countries are profiled here: Region 3
Middle East and Indian Ocean
Pg. 203
Afghanistan
211
Comoros
216
France (Indian Ocean Islands)
222
Iran
230
Madagascar
236
Pakistan
241
Saudi Arabia
246
South Africa
252
Syria
257
Yemen
263
Brown, S.K., Sparks, R.S.J., Mee, K., Vye-Brown, C., Ilyinskaya, E., Jenkins, S.F., and Loughlin, S.C. (2015) Country and regional profiles of volcanic hazard and risk. In: S.C. Loughlin, R.S.J. Sparks, S.K. Brown, S.F. Jenkins & C. Vye-Brown (eds) Global Volcanic Hazards and Risk, Cambridge: Cambridge University Press.
This profile and the data therein should not be used in place of focussed assessments and information provided by local monitoring and research institutions.
Region 3: Middle East and Indian Ocean
Figure 3.1 The distribution of Holocene volcanoes through the Middle East and Indian Ocean region. The capital cities of the constituent countries are shown. Description Region 3: The Middle East and Indian Ocean comprises volcanoes throughout the Middle East, Madagascar and much of the west and south Indian Ocean. Twelve countries are represented in this region. All are included in this regional discussion. For individual country profiles for Australia see Region 5 and for India see Region 6.
This profile and the data therein should not be used in place of focussed assessments and information provided by local monitoring and research institutions.
Country Number of volcanoes Afghanistan 2 Australia (See Region 5) 2 Comoros 2 France 9 India (See Region 6) 1 Iran 8 Madagascar 5 Pakistan 1 Saudi Arabia 10 South Africa 2 Syria 6 Yemen 8 + 4 from Region 2 Table 3.1 The countries represented in this region and the number of volcanoes. Volcanoes located on the borders between countries are included in the profiles of all countries involved. Note that countries may be represented in more than one region, as overseas territories may be widespread.
Figure 3.2 The Middle East section of Region 3. Fifty-six Holocene volcanoes are located in the Middle East and Indian Ocean. Most of these volcanoes are in Saudi Arabia (10), and indeed, most volcanoes are Middle Eastern, with fewer in the
204
Indian Ocean. A range of tectonic settings are represented here, from dominantly rift-related volcanism in the Middle East to intra-plate hotspot volcanoes in the Indian Ocean. Volcanoes with a range of morphologies are present in this region, with small cones dominating throughout Syria, Saudi Arabia, Yemen and Madagascar. Large cones, mainly stratovolcanoes, dominate in Iran and the French and Australian Indian Ocean islands. 36 out of 56 volcanoes are of basaltic composition. A range of activity has been recorded in the Middle East and Indian Ocean during the Holocene. 252 confirmed eruptions are recorded in this region, of VEI 0 to 5, representing small to large explosive eruptions. However, about 97% of eruptions have been small VEI 0 to 2 size events, with less than 1% of eruptions (just 1 event) being VEI ≥4. This VEI 5 event was the 2700 BC eruption of Piton de la Fournaise on the French island of Réunion. The absence of more VEI ≥4 eruptions may represent the limited geological stratigraphic studies of the volcanoes. Eleven volcanoes have historical records of 225 eruptions, of which 223 were recorded through direct observations. 76% of these eruptions have records of producing lava flows. No pyroclastic flows are recorded historically and just one lahar is recorded, at Karthala in the Comoros in 2005. The eruption record is dominated by historical events and eruptions of Piton de la Fournaise and Karthala, which make up 90% of the historical record. Just 2% of historical eruptions have resulted in loss of life. This is likely due to the small nature of most eruptions here, with lava flows rarely being the cause of fatalities. The size of the local population at the volcanoes of this region varies from low to high, with a corresponding range of assigned risk levels. Assessment of hazard (VHI) for all but four volcanoes is complicated by large uncertainties due to sparse eruption records. The two most frequently active volcanoes in this region, Karthala and Piton de la Fournaise have monitoring systems in place. Volcano facts Number of Holocene volcanoes
56
Number of Pleistocene volcanoes with M≥4 eruptions
4
Number of volcanoes generating pyroclastic flows
1 (1 eruption)
Number of volcanoes generating lahars
1 (1 eruption)
Number of volcanoes generating lava flows
15 (187 eruptions)
Number of eruptions with fatalities
5
Number of fatalities attributed to eruptions
53
Largest recorded Pleistocene eruption
The largest recorded explosive eruption in this region occurred at 26 ka, with the M6.7 Trachytic Ignimbrite eruption in the Kerguelen Islands. The 205
Kerguelen Islands are a French territory. Largest recorded Holocene eruption
The largest Holocene eruption was that of Piton de la Fournaise with the M5.3 Bellecombe Ash eruption of 4650 BP.
Number of Holocene eruptions
252 confirmed Holocene eruptions
Recorded Holocene VEI range
0 – 5 and unknown
Number of historically active volcanoes
11
Number of historical eruptions
225
Number of volcanoes 6
Primary volcano type
Dominant rock type
Large cone(s)
Andesitic (5), Basaltic (1)
1
Lava dome(s)
Andesitic (1)
6
Shield(s)
Basaltic (6)
33
Small cone(s)
Basaltic (29), Dacitic (1), Foiditic (1), Trachytic/Andesitic (1), Unknown (1)
1
Submarine
Unknown (1)
Table 3.2 The volcano types and dominant rock types of the volcanoes of this region according to VOTW4.0. Eruption Frequency VEI Recurrence Interval (Years) Small (< VEI 4) 1 Large (> VEI 3) Table 3.3 Average recurrence interval (years between eruptions) for small and large eruptions in the Middle East and Indian Ocean. The eruption record indicates that on average small to moderate sized eruptions of VEI